Mercury-lamp



H. GEORGE,

MERCURY LAMP.

APPLICATION FILED APR. 4. 1919.

- PaIeIea Nw, 29. 1921.

I. 1 Ik.

A'TNT OFFICE.

HENRI GEORGE, OF PARIS, FRANCE. i

MERCURY-LAMP.

Be it known that I. Hnxiu (nonon. citizenoi the French Republic.residing at lai'is. France, have iented certain new and usefulImprovements in 'Mei'cury-Lamps. ot' which the following is aspecilication.

This invention has for its object to provide an improved mercury vaporquartz lamp.

The accompanying drawing illustrates by way of example a constructions]torni ot an improved lamp.

1 is the illuminating tube in which the are is formed.

2 is the reservoir for the mercury cathode.

3 is the reservoir for the mercury anode.

4 is the negative terminal; and

5 is the positive terminal ot the lamp.

On the reservoir 25 there is formed a connecting conduit o that carriesthe two vessels 7 and S. A passage or tube (3 unites the reservoir 3with the tube (S. This tube 6 permits circulation ot' the mercury vaporthrough the path 1, il, S, 15. 3 and 1. The vessel 8 is connected to theupper end ofv the illuminating tube by a tube 9 of at least 4: mm.internal diameter. 0n the inside of the vessel 8 there is i'ormeda smallstraight tube 1() which is pierced with a hole 11 and contains atungsten wire 12 wound in the form of a helix. This wire is connect-edat its upper end to the terminal 5 and its lower end is immersed in themercury ot' the lamp and is connected to a terminal ring 12 seatedagainst the lower end of the tube 10 and. acting to hold the wire rigid.This wire serves both as an electrode and as a starting device ashereinafter described. The tube 1() extends in the lower tubular portion15 oi the vessel 8, leaving a small annular space between the two tubes.The vessel 7 has a constricted portion 13 of a diameter or' about 8/ 10mm. only. The level of the mercury in the lamp when at rest is indicatedat 11.

Above` the mercury, instead of a vacuum, there is an atmosphere of inertgas (such as, nitrogen, argon, neon, etc., preferably neon) at a highpressure of the order ot 70 mm. of mercury. When this gas has beenintroduced, the lamp is completely sealed up.

The operation is as follows:

The lamp having been iixed horizontally on its support, it is connectedto the terminals of a continuous circuit comprising a series-connectedrheostat 16. For the type 115l volts, this rheostat 16 is so adjusted asSpecification of Letters Patent. Patented NOV, 29, i921.

1919. Serial No. 287,554.

to pass twelve an'iperes into the circuit when the cut-out switch isclosed. At the moment when the current passes into the lamp, thetungsten wire l2 which. has a diameter of 1 /1() mm., is renderedincandescent. The gas illing the vessel 8 will then expand and force themercury both into the lower tube 15 and to the top of the illuminatingtube 1. The mercury thus forced back will accumulate in the vessel 7passing through the hole 13 which has tor object to deaden theoscillations of the mercury. column forced back by 'the gas is soonsevered at the top ot' the tube 1, and the arc then forms immediately.To ignite the lamp it is merely necessary to Aclose the cutout switchand to wait for 5 to 10 seconds. The formed arc continues to lengthenand assumes as its normal position the position` marked by the twopoints A and B. At this vinstant for the type 115 volts, the currentstrength is 4 amperes and the voltage at the terminals is 85 volts.lVhen the current is out ofi, the arc is extinguished. The inercurywhich stood at the level A, risesagain The mercury in the illuminatingtube and in the tube 15 at the same time as itsinks in the vessel 7, andthe general level 14 is restahlished after the lapse of a few seconds.

lt is essential that the gas that serves for starting the. lamp (neongives the best results) shall be eliminated from the illuminating tubeduring the operation of the lamp, because its presence in the said tubewould greatly diminish the etliciency of the lamp. vThis elimination isassured by they following means:

The mercury vapor which is generated abundantly in the arc, passesthrough the tube 9 and is condensedin the vessel 8, and

falls back between tubes .10 andl for supplying the anode. There is.thereiore a continuous circulation of mercury vapor along the path 1,9,8, 15, 6, 3, 1, 9. The mercury vapor passing through these tubeseliminates completely every trace of the gas, and assures to the arc theefficiency of a mercury arc in mercury vapor. The gas serving forstarting the lamp is thus completely confinedl -in the vessel 8 duringthe operation of .the lamp.

This circulation of the mercury assures at the same time thelequilibrium of the lamp from the point of view of vaporization andcondensation. I y

It is essential that the starting and disroo tilling tube 9 shall nothave a too small diameter in order that the mercury which is condensedtherein shall not choke it. In such a case there would be no longer anyequilibrium between the atmosphere of the arc and that of the vessel 8,and the result would be t0 produce sudden movements of the mercury thatmight extinguish the arc.

The cathode and anode reservoirs 2 and 3 are arranged in the axis of'the lamp in order n ot to throw any shadows during its operation.

It is to be noted that the hole 18 for deadening the oscillations issituated at a point outside of the path of the current, so that there isno risk of the flow of the current be- ,ing'interrupted by the lodgingof a bubble of gasl at that point.

MDuring the transport of the lamp the gas is able to mix with themercury or to displace it. Consequently it is necessary to restore thegas to its proper place before lighting the lamp which has been carriedfor some considerable distance. For the purpose of :facilitating thisoperation the vessels 7 and 8 are mounted side by side on the connectingconduit 6 which establishes connection between their lower ends. The operation is further facilitated by the two fold communication 9 and 15between the gas vessel 8 and the illuminating tube.

In connection with the foregoing it is to be understood that the liliesA and B do not indicate the mercury levels which are naturallyhorizontal and which passl through the central point of these lines butit is apparent from the specification that said lines A and B indicatethe sections of the tube between which the axis is formed during normaloperation. A

The lamp as described, can be started and operated with alternatingcurrent. The nec# essary minimum voltage for starting is in this case500 volts. It is necessary to provide a self-induction in series.

The characteristic advantages of this lamp are:

1. An automatic ignition without rocking. 2. A higher efficiency.

3. Owing to the fact that the pressure is high even in the cold state,the' placing of the lamp in operative order is instantaneous, and thelamp ygive-s 'its full luminous intensity immediately on starting. Alsoow ing to this fact, the lamp is not affected by atmospheric influences.

4. Owing to no vacuum being used, the risk of iii-leaking of air and ofbreaking through mercury hammer is avoided.

The improved lamp can be worked with alternating current.

Having now particularly described and ascertained the nature of my saidinvention and in what manner the same isto be performed, I declare thatwhat 'I claim is 1.' A mercury vapor quartz lamp, including anilluminating tube, a mercury cathode and in circuit with said cathodereservoir,

a pair of communicating vessels carried by one of said reservoirs, andIone of said vessels communicating with said tube and containing anatmosphere of inert gas at a high pressure of the order of atmosphericpressure, substantially as described.

2. A mercury vapor quartz lamp including an illuminating tube, a mercurycathode reservoir communicating with one end of said tube, a mercuryanode reservoir communicating with the other end of said tube, a pair ofcommunicating vessels carried by the anode chamber one of which isadapt-ed to contain a 'supply of inert gas while the other serves toreceive the mercury forced out of the illuminating tube when the lamp isin operation, another tube between the gas containing vessel and theilluminating tube, a positive terminal mounted in the gascontainingvessel and serving as an igniting means for the lamp, and a negativeterminal connected with the cathode chamber and in circuit with thepositive terminal.

3. A` mercury vapor lamp as claimed in claim 2 wherein a small tube isjoined with the top of the gas containing vessel and terminating shortof the lower end thereof,

and the lower portion of the positive termi-- 4. In a mercury vapor lamphaving an atmosphere of inert gas under high pressure, the arrangementlaterally with respect to an anode reservoir of an auxiliary reservoirclosed at its upper part and communicating with the anode reservoir, an.axial tube integral with the upper end ot said reservoir and open atthe lower part so as to be immersed in the mercury, the tube beingprovided with an opening at the upper part causing communication of thelatter with the reservoir which surrounds it, a Spiral tungsten wireconnected to the positive pole of the circuit and arranged in said tubeto assure the electrical connection with the Inercury contained in theanode'reservoir, and

means for assu ring the continuous and automatic circulation of themercury between the anode reservoir and said auxiliary reservoir.

5. In a mercury vapor lam-@with 'nert gas atmosphere under highpressure,- the arrangement laterally with respect to an anode reservoir,ot' an auxiliary reservoir closed at its upper end and communicatingwith the anode reservoir. an axial tube integral witlithe end of saidlast mentioned reservoir and open at its lower part so as to be im-'mersed in the mercury, the tube being provided with-an opening at theupper part es;

tablishing communication of said latter with tube in which the arcplays, for the purpose of creating an automa-tic continuous circu-`lation of the mercury between thel `anode reservoir and said auxiliaryVreservoir, and means to collect the mercury at the moment of thebeginningl of the priming of the tube.

6. In a mercury vapor lamp with an atmosphere of inert gas under highpressure,

` the arrangement, laterally with respect to an anode reservoir, of anauxiliary. reservoir closed at 'its upper part and communicating withsaid latter, an axial tube integral with the bottom end of saidreservoir and open at its lower part so as to be immersed in themercury, the tube being provided with an opening at the upper part forestablishing communication thereof with the interior of the reservoirwhich surrounds it, a tungsten wire spiralconnecte'd to the positivepole of the circuit apd arranged in said tube to assure the electricalconnection with the mercury containe/d in the anode reservoir, a pas-Sage establishing communica-tion of said auxilia vill lWhiiiii reservoirwith the part oi' the tube the arc plays, another auxiliary terior ofsai reservoir closed at its upper part and its lower partcommuni(eatingY with the first named' auxiliary reservoir and the anodereservoir to collect the mercury at the moment at which the arc begins,-and means to prevent 'the introduction of bubbles of gas in saidymercury collecting rservoir.A

7. In a mercury va por lamp `having an atmosphere of inert gas underhigh pressure,

the arrangement laterally of an anode reservoir, of an auxiliaryreservoir?? closed atits upper .part and communicating,r with saidlatter, an axial tube integral with the bottom end of said reservoir andopen at its lower end so as to be immersed in the mercury, the

tube being provided with an opening at the A upper part of ,said tube toestablish communication between the latter and the intungsten wire'spiral connected to the positive pole of the cixicuit and arranged insaid tube to assure electirical connection with the mercury contained-inthe anode reservoir, a passage establishing communication between saidauxiliary reservoir land the 1.- rt 'of the tube in which the arc plays,another auxiliary reservoir closed at its upper part, the lower partcommunicating with the .first auxiliary reservoir and the anodereservoir, a perforated diaphragm arranged at the entrance of saidreservoir Jfor the purpose of preventing entrance of gas bubbles whenthe. level ot the mercury varies in said latter.

In testimony whereo` 1 affix my signature.

HENRI GEORGE.

reservoir surrounding it, a'

